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Diffstat (limited to 'sha1_file.c')
-rw-r--r--sha1_file.c259
1 files changed, 139 insertions, 120 deletions
diff --git a/sha1_file.c b/sha1_file.c
index d880137ef4..3401301444 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -383,7 +383,7 @@ void add_to_alternates_file(const char *reference)
{
struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
- char *alt = mkpath("%s/objects\n", reference);
+ char *alt = mkpath("%s\n", reference);
write_or_die(fd, alt, strlen(alt));
if (commit_lock_file(lock))
die("could not close alternates file");
@@ -837,7 +837,7 @@ static int in_window(struct pack_window *win, off_t offset)
unsigned char *use_pack(struct packed_git *p,
struct pack_window **w_cursor,
off_t offset,
- unsigned int *left)
+ unsigned long *left)
{
struct pack_window *win = *w_cursor;
@@ -1189,7 +1189,7 @@ static int open_sha1_file(const unsigned char *sha1)
return -1;
}
-static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
+void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
{
void *map;
int fd;
@@ -1208,20 +1208,49 @@ static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
return map;
}
-static int legacy_loose_object(unsigned char *map)
+/*
+ * There used to be a second loose object header format which
+ * was meant to mimic the in-pack format, allowing for direct
+ * copy of the object data. This format turned up not to be
+ * really worth it and we no longer write loose objects in that
+ * format.
+ */
+static int experimental_loose_object(unsigned char *map)
{
unsigned int word;
/*
- * Is it a zlib-compressed buffer? If so, the first byte
- * must be 0x78 (15-bit window size, deflated), and the
- * first 16-bit word is evenly divisible by 31
+ * We must determine if the buffer contains the standard
+ * zlib-deflated stream or the experimental format based
+ * on the in-pack object format. Compare the header byte
+ * for each format:
+ *
+ * RFC1950 zlib w/ deflate : 0www1000 : 0 <= www <= 7
+ * Experimental pack-based : Stttssss : ttt = 1,2,3,4
+ *
+ * If bit 7 is clear and bits 0-3 equal 8, the buffer MUST be
+ * in standard loose-object format, UNLESS it is a Git-pack
+ * format object *exactly* 8 bytes in size when inflated.
+ *
+ * However, RFC1950 also specifies that the 1st 16-bit word
+ * must be divisible by 31 - this checksum tells us our buffer
+ * is in the standard format, giving a false positive only if
+ * the 1st word of the Git-pack format object happens to be
+ * divisible by 31, ie:
+ * ((byte0 * 256) + byte1) % 31 = 0
+ * => 0ttt10000www1000 % 31 = 0
+ *
+ * As it happens, this case can only arise for www=3 & ttt=1
+ * - ie, a Commit object, which would have to be 8 bytes in
+ * size. As no Commit can be that small, we find that the
+ * combination of these two criteria (bitmask & checksum)
+ * can always correctly determine the buffer format.
*/
word = (map[0] << 8) + map[1];
- if (map[0] == 0x78 && !(word % 31))
- return 1;
- else
+ if ((map[0] & 0x8F) == 0x08 && !(word % 31))
return 0;
+ else
+ return 1;
}
unsigned long unpack_object_header_buffer(const unsigned char *buf,
@@ -1248,7 +1277,7 @@ unsigned long unpack_object_header_buffer(const unsigned char *buf,
return used;
}
-static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
+int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
{
unsigned long size, used;
static const char valid_loose_object_type[8] = {
@@ -1265,37 +1294,32 @@ static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned lon
stream->next_out = buffer;
stream->avail_out = bufsiz;
- if (legacy_loose_object(map)) {
- git_inflate_init(stream);
- return git_inflate(stream, 0);
- }
-
+ if (experimental_loose_object(map)) {
+ /*
+ * The old experimental format we no longer produce;
+ * we can still read it.
+ */
+ used = unpack_object_header_buffer(map, mapsize, &type, &size);
+ if (!used || !valid_loose_object_type[type])
+ return -1;
+ map += used;
+ mapsize -= used;
- /*
- * There used to be a second loose object header format which
- * was meant to mimic the in-pack format, allowing for direct
- * copy of the object data. This format turned up not to be
- * really worth it and we don't write it any longer. But we
- * can still read it.
- */
- used = unpack_object_header_buffer(map, mapsize, &type, &size);
- if (!used || !valid_loose_object_type[type])
- return -1;
- map += used;
- mapsize -= used;
+ /* Set up the stream for the rest.. */
+ stream->next_in = map;
+ stream->avail_in = mapsize;
+ git_inflate_init(stream);
- /* Set up the stream for the rest.. */
- stream->next_in = map;
- stream->avail_in = mapsize;
+ /* And generate the fake traditional header */
+ stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
+ typename(type), size);
+ return 0;
+ }
git_inflate_init(stream);
-
- /* And generate the fake traditional header */
- stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
- typename(type), size);
- return 0;
+ return git_inflate(stream, 0);
}
-static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
+static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
{
int bytes = strlen(buffer) + 1;
unsigned char *buf = xmallocz(size);
@@ -1345,7 +1369,7 @@ static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size
* too permissive for what we want to check. So do an anal
* object header parse by hand.
*/
-static int parse_sha1_header(const char *hdr, unsigned long *sizep)
+int parse_sha1_header(const char *hdr, unsigned long *sizep)
{
char type[10];
int i;
@@ -1394,7 +1418,7 @@ static int parse_sha1_header(const char *hdr, unsigned long *sizep)
static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
{
int ret;
- z_stream stream;
+ git_zstream stream;
char hdr[8192];
ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
@@ -1410,7 +1434,7 @@ unsigned long get_size_from_delta(struct packed_git *p,
{
const unsigned char *data;
unsigned char delta_head[20], *in;
- z_stream stream;
+ git_zstream stream;
int st;
memset(&stream, 0, sizeof(stream));
@@ -1484,7 +1508,7 @@ static off_t get_delta_base(struct packed_git *p,
/* forward declaration for a mutually recursive function */
static int packed_object_info(struct packed_git *p, off_t offset,
- unsigned long *sizep);
+ unsigned long *sizep, int *rtype);
static int packed_delta_info(struct packed_git *p,
struct pack_window **w_curs,
@@ -1498,7 +1522,7 @@ static int packed_delta_info(struct packed_git *p,
base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
if (!base_offset)
return OBJ_BAD;
- type = packed_object_info(p, base_offset, NULL);
+ type = packed_object_info(p, base_offset, NULL, NULL);
if (type <= OBJ_NONE) {
struct revindex_entry *revidx;
const unsigned char *base_sha1;
@@ -1526,13 +1550,13 @@ static int packed_delta_info(struct packed_git *p,
return type;
}
-static int unpack_object_header(struct packed_git *p,
- struct pack_window **w_curs,
- off_t *curpos,
- unsigned long *sizep)
+int unpack_object_header(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t *curpos,
+ unsigned long *sizep)
{
unsigned char *base;
- unsigned int left;
+ unsigned long left;
unsigned long used;
enum object_type type;
@@ -1552,63 +1576,8 @@ static int unpack_object_header(struct packed_git *p,
return type;
}
-const char *packed_object_info_detail(struct packed_git *p,
- off_t obj_offset,
- unsigned long *size,
- unsigned long *store_size,
- unsigned int *delta_chain_length,
- unsigned char *base_sha1)
-{
- struct pack_window *w_curs = NULL;
- off_t curpos;
- unsigned long dummy;
- unsigned char *next_sha1;
- enum object_type type;
- struct revindex_entry *revidx;
-
- *delta_chain_length = 0;
- curpos = obj_offset;
- type = unpack_object_header(p, &w_curs, &curpos, size);
-
- revidx = find_pack_revindex(p, obj_offset);
- *store_size = revidx[1].offset - obj_offset;
-
- for (;;) {
- switch (type) {
- default:
- die("pack %s contains unknown object type %d",
- p->pack_name, type);
- case OBJ_COMMIT:
- case OBJ_TREE:
- case OBJ_BLOB:
- case OBJ_TAG:
- unuse_pack(&w_curs);
- return typename(type);
- case OBJ_OFS_DELTA:
- obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
- if (!obj_offset)
- die("pack %s contains bad delta base reference of type %s",
- p->pack_name, typename(type));
- if (*delta_chain_length == 0) {
- revidx = find_pack_revindex(p, obj_offset);
- hashcpy(base_sha1, nth_packed_object_sha1(p, revidx->nr));
- }
- break;
- case OBJ_REF_DELTA:
- next_sha1 = use_pack(p, &w_curs, curpos, NULL);
- if (*delta_chain_length == 0)
- hashcpy(base_sha1, next_sha1);
- obj_offset = find_pack_entry_one(next_sha1, p);
- break;
- }
- (*delta_chain_length)++;
- curpos = obj_offset;
- type = unpack_object_header(p, &w_curs, &curpos, &dummy);
- }
-}
-
static int packed_object_info(struct packed_git *p, off_t obj_offset,
- unsigned long *sizep)
+ unsigned long *sizep, int *rtype)
{
struct pack_window *w_curs = NULL;
unsigned long size;
@@ -1616,6 +1585,8 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
enum object_type type;
type = unpack_object_header(p, &w_curs, &curpos, &size);
+ if (rtype)
+ *rtype = type; /* representation type */
switch (type) {
case OBJ_OFS_DELTA:
@@ -1645,7 +1616,7 @@ static void *unpack_compressed_entry(struct packed_git *p,
unsigned long size)
{
int st;
- z_stream stream;
+ git_zstream stream;
unsigned char *buffer, *in;
buffer = xmallocz(size);
@@ -1698,6 +1669,13 @@ static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
return hash % MAX_DELTA_CACHE;
}
+static int in_delta_base_cache(struct packed_git *p, off_t base_offset)
+{
+ unsigned long hash = pack_entry_hash(p, base_offset);
+ struct delta_base_cache_entry *ent = delta_base_cache + hash;
+ return (ent->data && ent->p == p && ent->base_offset == base_offset);
+}
+
static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
unsigned long *base_size, enum object_type *type, int keep_cache)
{
@@ -1842,6 +1820,24 @@ static void *unpack_delta_entry(struct packed_git *p,
return result;
}
+static void write_pack_access_log(struct packed_git *p, off_t obj_offset)
+{
+ static FILE *log_file;
+
+ if (!log_file) {
+ log_file = fopen(log_pack_access, "w");
+ if (!log_file) {
+ error("cannot open pack access log '%s' for writing: %s",
+ log_pack_access, strerror(errno));
+ log_pack_access = NULL;
+ return;
+ }
+ }
+ fprintf(log_file, "%s %"PRIuMAX"\n",
+ p->pack_name, (uintmax_t)obj_offset);
+ fflush(log_file);
+}
+
int do_check_packed_object_crc;
void *unpack_entry(struct packed_git *p, off_t obj_offset,
@@ -1851,6 +1847,9 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
off_t curpos = obj_offset;
void *data;
+ if (log_pack_access)
+ write_pack_access_log(p, obj_offset);
+
if (do_check_packed_object_crc && p->index_version > 1) {
struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
unsigned long len = revidx[1].offset - obj_offset;
@@ -2078,7 +2077,7 @@ static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *size
int status;
unsigned long mapsize, size;
void *map;
- z_stream stream;
+ git_zstream stream;
char hdr[32];
map = map_sha1_file(sha1, &mapsize);
@@ -2096,24 +2095,28 @@ static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *size
return status;
}
-int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
+/* returns enum object_type or negative */
+int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
{
struct cached_object *co;
struct pack_entry e;
- int status;
+ int status, rtype;
co = find_cached_object(sha1);
if (co) {
- if (sizep)
- *sizep = co->size;
+ if (oi->sizep)
+ *(oi->sizep) = co->size;
+ oi->whence = OI_CACHED;
return co->type;
}
if (!find_pack_entry(sha1, &e)) {
/* Most likely it's a loose object. */
- status = sha1_loose_object_info(sha1, sizep);
- if (status >= 0)
+ status = sha1_loose_object_info(sha1, oi->sizep);
+ if (status >= 0) {
+ oi->whence = OI_LOOSE;
return status;
+ }
/* Not a loose object; someone else may have just packed it. */
reprepare_packed_git();
@@ -2121,15 +2124,31 @@ int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
return status;
}
- status = packed_object_info(e.p, e.offset, sizep);
+ status = packed_object_info(e.p, e.offset, oi->sizep, &rtype);
if (status < 0) {
mark_bad_packed_object(e.p, sha1);
- status = sha1_object_info(sha1, sizep);
+ status = sha1_object_info_extended(sha1, oi);
+ } else if (in_delta_base_cache(e.p, e.offset)) {
+ oi->whence = OI_DBCACHED;
+ } else {
+ oi->whence = OI_PACKED;
+ oi->u.packed.offset = e.offset;
+ oi->u.packed.pack = e.p;
+ oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
+ rtype == OBJ_OFS_DELTA);
}
return status;
}
+int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
+{
+ struct object_info oi;
+
+ oi.sizep = sizep;
+ return sha1_object_info_extended(sha1, &oi);
+}
+
static void *read_packed_sha1(const unsigned char *sha1,
enum object_type *type, unsigned long *size)
{
@@ -2427,7 +2446,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
{
int fd, ret;
unsigned char compressed[4096];
- z_stream stream;
+ git_zstream stream;
git_SHA_CTX c;
unsigned char parano_sha1[20];
char *filename;
@@ -2444,7 +2463,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
/* Set it up */
memset(&stream, 0, sizeof(stream));
- deflateInit(&stream, zlib_compression_level);
+ git_deflate_init(&stream, zlib_compression_level);
stream.next_out = compressed;
stream.avail_out = sizeof(compressed);
git_SHA1_Init(&c);
@@ -2452,8 +2471,8 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
/* First header.. */
stream.next_in = (unsigned char *)hdr;
stream.avail_in = hdrlen;
- while (deflate(&stream, 0) == Z_OK)
- /* nothing */;
+ while (git_deflate(&stream, 0) == Z_OK)
+ ; /* nothing */
git_SHA1_Update(&c, hdr, hdrlen);
/* Then the data itself.. */
@@ -2461,7 +2480,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
stream.avail_in = len;
do {
unsigned char *in0 = stream.next_in;
- ret = deflate(&stream, Z_FINISH);
+ ret = git_deflate(&stream, Z_FINISH);
git_SHA1_Update(&c, in0, stream.next_in - in0);
if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
die("unable to write sha1 file");
@@ -2471,7 +2490,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
if (ret != Z_STREAM_END)
die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
- ret = deflateEnd(&stream);
+ ret = git_deflate_end_gently(&stream);
if (ret != Z_OK)
die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
git_SHA1_Final(parano_sha1, &c);
@@ -2707,7 +2726,7 @@ static int index_stream(unsigned char *sha1, int fd, size_t size,
while (size) {
char buf[10240];
size_t sz = size < sizeof(buf) ? size : sizeof(buf);
- size_t actual;
+ ssize_t actual;
actual = read_in_full(fd, buf, sz);
if (actual < 0)
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-30 13:21:41 +0000